﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ex6
{
    class Program
    {
        static void Main(string[] args)
        {
            double a, b, c;
            //string s = Console.ReadLine();
            var s = Console.ReadLine();
            var ss = s.Split(' ');
            a = Convert.ToDouble(ss[0]);
            b = Convert.ToDouble(ss[1]);
            c = Convert.ToDouble(ss[2]);
            if (a + b > c && b + c > a && a + c > b)
            {
                Console.WriteLine("yes");
            }
            else
            {
                Console.WriteLine("no");
            }
  
        }
    }
}
